Formation of igloos, for shelter and for recreation, is well known. Typically blocks of snow are formed and stacked into a dome like structure; however, due to the inclination of the walls as the dome structure is formed, it is commonly difficult for unskilled persons to properly align the blocks so that they remain in place during construction.
Various tools are known for assisting in the construction of an igloo. U.S. Pat. No. 6,210,142 belonging to Huesers and U.S. Pat. No. 4,154,423 belonging to Crock disclose examples of tools to assist construction of an igloo type structure.
Huesers discloses a complex linkage apparatus for locating the blocks during construction; however, the complex arrangement of the linkage connected to a pivot anchor is awkward to use in practice.
In Crock, a mold is provided for forming a single construction block which is intended to be similar to the shape of a conventionally formed block for forming an igloo. The mold surrounds both top and bottom sides of the finished block with the outer side of the block being the exposed side to permit releasing from the mold. In this construction, the block cannot be deposited from the mold into place in the igloo structure, but rather the block must first be released from the mold and then subsequently placed in position in the igloo structure under construction. The orientation of the tapering walls would not permit the blocks to be released directly from the mold into position in the assembled igloo structure. Furthermore, the smooth walls make it difficult to retain the block in place during construction.